Manufacture of hacksaw frame members



April 11, 1939. PR|E$T 2,154,009

MANUFACTURE OF HACKSAW FRAME MEMBERS Original Filed Sept. 18, 1935Patented Apr. 11, 1939 UNITED STATES PATENT OFFIQE MANUFACTURE OFHACKSAW FRAME MEMBERS Dwight E. Priest, Worcester, Mass, assignor toParker Wire Goods Company, Worcester, Mass, a corporation ofMassachusetts 2 Claims.

This application is a division of my parent application Serial No.41,113, filed September 18, 1935, Patent No. 2,058,107, the latterhaving matured as Reissue Patent No. 20,252, dated January 26, 1937, onan application filed Nov. 30, 1936, for Hacksaw frame construction; thepresent invention relates to the method of making certain hacksaw framemembers of my aforesaid patented hacksaw frame construction.

The frame members in question are those which support the retaining andtensioning devices for the saw blade,and an object of my invention is toimprove and simplify the manufacture of such members, and thus to makepossible the production of hacksaws and like devices which are stronger,more durable, and more satisfactory in operation than similar devices ofthis character now in ordinary use. Other and further objects andadvantages of the invention will be apparent from the following detaileddescription of the same, taken in connection with the accompanyingdrawing, in which Fig. 1 is a view in side elevation illustrating theimproved hacksaw which is shown, described and claimed in my aforesaidcopending application.

Fig. 2 is a fragmentary end view of parts shown in Fig. 1, on a somewhatlarger scale than Fig. 1.

Figs. 3, 4 and 5, are detail views illustrating successive steps in themanufacture of the adjustable end member of my improved hacksaw frameconstruction shown by Fig. 1.

Figs. 6 and 7 are detail views illustrating successive steps in themanufacture of the other end member of said frame.

Fig. 8 is a view similar to Fig. 7, illustrating a modification of theinvention.

Like reference characters refer to like parts in the different figures.

Referring first to Figs. 1 and 2, illustrating the improved saw assemblyof my aforesaid copending application, the saw frame is constituted byan intermediate elongated member I, substantially parallel to the sawblade 2 and of downwardly opening channel section, and by two endmembers 3 and 4. The outer end member 3 (here shown as the adjustablemember of the frame) is of bent or curved form to provide asubstantially horizontal portion 5 received in the channel of member I,and a substantially vertical portion 6, adapted to carry at its lowerend one of the devices I for securing and tensioning the saw blade 2 inthe frame. Said horizontal portion 5 of member 3 is provided along itslower edge with a plurality of notches 8, 8, adapted to cooperate with apin 9 extending across member I; when the saw blade is being put inplace, the member 3 can be moved in or out, as desired, to bring anyselected notch 8 into engagement with pin 9, thereby to make the lengthof the frame appropriate to the length of the blade which is to be usedtherein. The other or inner end member 4 is of bent or curved form toprovide a depending leg portion Ill adapted to carry at its lower endthe other device 1 for securing and tensioning the saw blade, and alsoto provide a second depending leg ll adapted to be embedded by thehandle l2. Between said two depending-leg portions l0 and H, said memberl 1 has a substantially horizontal portion I3 received in the channel ofmember I, and secured rigidly thereto by rivets, welding, or the like,as indicated at I4.

Heretofore, in the manufacture of hacksaw frames of the general typeabove 'set forth, it has been the practice to make the end members,(corresponding substantially to the members 3 and 4 above), from stockof relatively wide flat section in order to obtain the requisitestiffness for said members in the plane of the frame without undulyincreasing the latters weight; such stock, after being cut to the lengthrequired for such an end member, has to be bent to provide the dependinglegs 6 or Ill, as the case may be, an operation that is attended withconsiderable difficulty, as well as with risk of spoiling or deformingthe stock, because the outer edge of the bend is necessarily on a muchgreater radius than the inner edge of the bend. The bending of such flatstock across its width or greatest sectional dimension causes unduestretch of the material at the outer edge of the bend and unduecompression of the material at the inner edge of the bend; this may wellresult in internal stresses and strains that seriously affect thestrength of the frame member. It has also been proposed, with a framemember made from such wide flat stock, to impart to such stock, at thelower extremity of said member, a 90 twist, thereby to give sufficientwidth of stock at the extremity of the leg for an aperture adapted toreceive the saw blade retaining device; such twisting of the fiat stock,even though confined to the extremity of the leg, materially reduces thestrength and stiffness of the frame member in the plane of the saw.

According to my invention, the end members 3 and 4 of the saw frame,instead of being made by the bending to appropriate form of stock thatis already rolled or otherwise fabricated to the desired wide flat crosssectional form, are made from stock which is readily bendable, forexample, wire rod stock of substantially round cross section; theprocedure with a piece of such stock, out to appropriate length, isfirst to provide the bend and then to subject the bent piece to theappropriate flattening operation or operations for so altering itssection as to give the frame the requisite stiffness.

For example, referring to Figs. 3, 4 and 5, the production, according tomy invention, of the end member 3 involves the use of a piece [5 ofround rod stock of the required length, the first operation on which isto bend it so as to provide the respective horizontal and verticalportions 5' and 6; thereupon, the bent piece is subjected to a pressing,rolling or hammering operation by which to flatten out the horizontalportion 5' and also most of the length of the leg 6', as shown in Fig.4. Another pressing, rolling or hammering operation is availed of toflatten out, in a plane substantially at right angles to the flattenedportions of Fig. 4, the lower extremity of leg 6, as shown at l6, Fig.5,this flattened portion l6 thus presenting a stock section which isample in width, crosswise of the plane of the saw frame, to have formedtherein a suitable socket or hole I1, Fig. 2, for directly receiving thetensioning device I for the saw blade.

Similarly, for the production of the end member 4, an appropriate lengthof wire rod stock is first bent (see Fig. 6) to provide the dependingdivergent portions l0 and H and the intermediate horizontal portion l3;then, as shown in Fig. '7, by suitable pressing or hammering operations,the portion l3 and most of the length of portion [0' are flattened outto give the requisite stiffness to said member in the plane of theframe, and another flattening operation is performed on the extremity ofleg I0, in a plane at right angles to the first-mentioned flattening, toprovide a terminal portion [8 matching the portion l6 of member 3, andof sufiicient width, crosswise of the saw frame, to have formed thereina socket or aperture I9 adapted to directly receive the blade retainingdevice I. As shown in Fig.8, the first-mentioned flattening operation onthe stock for member 4 may include the leg portion II which is adapted,as shown by Fig. 1, to be embedded in the handle l2 of the saw. Suchflattening, as shown at 20, Fig. 8, permits the formation of holes 2|,2| to receive screws, rivets, or the like, by which the halves of atwo-part or split handle, not shown, may be secured to each other and tothe member 4.

I claim,

1. In the manufacture of a hacksaw frame member, having a handle portionand a depending leg portion, the latter at its extremity adapted toreceive a saw-blade retaining device, the improvement which consists ininitially forming two bends in a piece of substantially round rod stockto provide said handle portion and said leg portion in proper angularrelation to the remainder of said piece, and thereafter flattening saidhandle portion and said leg portion, except at the latters extremity, ina longitudinal plane and flattening the leg portions extremity in atransverse plane, whereby to impart sufficient width to said legextremity for the passage therethrough of a saw-blade retaining device.

2. In the manufacture of a hacksaw frame member, having a longitudinallyextending portion and a depending leg portion, the latter at itsextremity adapted to receive a saw-blade retaining device, theimprovement which consists in initially forming a bend in a piece ofsubstantially round rod stock to provide said two portions in properangular relation to each other, and thereafter flattening saidlongitudinal portion and said leg portion, except at the lattersextremity, in a longitudinal plane, to increase the members resistanceto bending in the plane of the frame, and flattening the leg portionsextremity in a transverse plane, whereby to im part sufiicient width tosaid leg extremity for the passage therethrough of a saw-blade retainingdevice.

DWIGHT E. PRIEST.

